The traditional methods applied in improving the measurement accuracy of electronic belt scales are designing highly sensitive scales and improving the sampling accuracy of weighing sensor. These methods are difficult to compensate for the weighing errors caused by belt tension. However, the effect of belt tension on measurement accuracy can be reduced by setting up multiple scales in parallel and forming an array of scales. Based on the analysis of internal force theory, it is concluded that the belt tension at both ends of the electronic belt scale is the main cause of weighing errors, and the proportion of belt tension at both ends decreases with the increase of the weighing unit. Therefore, the array electronic belt scale can reduce the impact of belt tension changes on the measurement accuracy and improve stability. In this study, a networked high-precision and high-stability array electronic belt scale instrument is designed with high-performance ARM processor STM32F767 as the control core. The functions of the scale include 8-channel weighing array dynamic metering, logic control, human-machine interaction, power-down storage, industrial control & communication and Internet remote monitoring. By using static coding method, the test results show that the weighing error of the instrument is about 0.03%, the scale is insensitive to the tension changes caused by the belt speed and load, and the scale has high measurement accuracy and stability.
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